when to replace fan belts

I have put 300-400 thousand miles on OEM belts. This was on several trucks. Only time I would replace them was when an alternated idler or tensioner failed. When was the last time you saw a broken belt laying on the highway?

JKaz

As one poster mentioned the idler/s and tension pulley bearings are what goes long before the belt with normal usage. On an engine that gets little usage 7 years on rubber products is a good rule of thumb.

univmd wrote:
Our alternator seized and the belt snapped at 50,000 miles.

You can't blame that on the belt!

bass n bob wrote:
I have the Ford F53 Chassis with 30,000 miles. At what point should I think about getting the fan belt replaced? I can find no reference to it in the owner's manual. THX

Age, heat and dry cracking, upon inspection, might dictate more. If it's a modern single serpentine belt with a belt tensioner, then it could be good for 100K miles easily without the effects of aging.
Thing is, if you're not carrying a spare that you know will work, you should install a new one and keep the original on board for an emergency. Also learn to change it out in your driveway and carry along what you need, since it's a lot easier learning this at home, than it is, in the middle of Death Valley.

When I bought my '94 F53 Bounder in 2010 it had 46,000 miles on it, still had all original belts, hoses and plugs. When I removed the old belts they looked the same as the new belts except the old belts had most of the paint worn off the the flat side. The rad hoses were in perfect shape as well. I replaced everything as a matter of principle but I doubt I'll ever change anything again in the few years I'll own this thing.

I recentlly changed the belts on my car at 100,000 miles only because it called for it in the maintenance schedule, the old belts were all good.

If you're an old guy like me you remember the days when belts and hoses HAD to be replaced every couple of years or they WOULD fail, usually at night in the middle of nowhere, and this is before there were cell-phones.

I haven't had a belt or hose fail on any of my vehicles now for at least 25 years: I do change them, but not till they have at least 100,000 miles or more and the old parts never look like they're all used up.

If any doubt, change it and keep the old one as a spare. This is what I've done.

Our 2001 Went over 100,000 miles with the original belt and it was still in good condition when we traded it off. Many times in the dead of winter I would take it to the Ford truck garage for servicing rather than lay under it in the cold and snow. Every time I asked them to check the belts and hoses and replace them as necessary.

It seemed like an open invitation for someone to sell me something that I might not need. However it never happened. In all those years and all those miles they never suggested changing a belt or hose.

I did buy a spare belt at about the 6 year mark "just in case". It went with the motorhome still in the factory sleeve when we bought the new motorhome.

I changed the belt on my 99 V10 chassis when it was 10 years old and had about 60k miles.The only tool needed is a 1/2 inch breaker bar.On my mh it has to be accesed from underneath.Its not a bad job but I wouldn,t want to do it on a hot engine.Also the first belt the parts store gave was too short.Had to take the old one in and match it up.Glad I did it at home on a cold engine.

Has anyone had a good OEM belt break at 30,000 miles? How about under 60,000 miles?

I replaced the belt, tensioner and both idlers when we got our coach because it was at 98,000 miles, something was squeaking and I wanted to do it all at once. The belt was in very good shape but obviously weathered.

The belt change was extremely easy with a helper in the dog house but would be a little bit of a pain done alone. All you need is a 1/2 ratchet and preferably a small length of pipe to extend the handle. There is no way in heck I am putting a new belt on every 30,000 miles unless that mileage is over 7 years or so.

I'm scared of the plug threading on the '99 V10 so I'm not replacing those until I get misfire. Shoot, I just replaced plugs on my Mazda MPV at 90,000 miles and all the old needed was a quick blast of carb cleaner to look brand new.

I look at the belts this way.....they are NOT expensive, and it can be a big problem if one breaks. For that reason, I change them out at 30,000 miles, which for me is about every two years. This way I can change the belt in the comfort of my own shop and not on the side of the road somewhere.
In most vehicles when the belt breaks you lose power steering, the water pump for cooling, alternator, etc. This means that you can only go a very limited distance after it breaks and your coach will be next to impossible to steer. Then think about where you travel and Murphy's law, which means problems will happen at the worst possible time. Do you want to be stuck at the side of the road, or at a location where you can't even get off of the road? Sure you have a spare, but will it break at a location that you can replace it yourself?
Belts are just one of of those things that are too cheap to ignore and too important for your safety to extend their replacement until they fail.
I also use Gates belts after one of my Dayco belts failed at 15,000 miles.